Core/DataStores: Define one MapFlags3

Author: Shauren

src/server/game/DataStores/DB2Structure.h

@@ -2979,6 +2979,7 @@ struct MapEntry
 
     EnumFlag<MapFlags> GetFlags() const { return static_cast<MapFlags>(Flags[0]); }
     EnumFlag<MapFlags2> GetFlags2() const { return static_cast<MapFlags2>(Flags[1]); }
+    EnumFlag<MapFlags3> GetFlags3() const { return static_cast<MapFlags3>(Flags[2]); }
 };
 
 struct MapChallengeModeEntry

src/server/game/DataStores/DBCEnums.h

@@ -1638,6 +1638,13 @@ enum class MapFlags2 : uint32
 
 DEFINE_ENUM_FLAG(MapFlags2);
 
+enum class MapFlags3 : uint32
+{
+    IsDelve = 0x00000100,
+};
+
+DEFINE_ENUM_FLAG(MapFlags3);
+
 enum class MapDifficultyFlags : uint8
 {
     LimitToPlayersFromOneRealm              = 0x01,